Ensure ISM Configs are all objects (no more `Address`)

[paulbalaji]

Currently the IsmConfig type states that configs can be an Address - which is just a string. We should remove this and ensure all ISM configs are objects containing type at the very least https://github.com/hyperlane-xyz/hyperlane-monorepo/blob/03ca2d1df76a7654450b71bf5bf80c40842b58e0/typescript/sdk/src/ism/types.ts#L104

MVP idea:

• update to object containing type and address

export type IsmAddressConfig = {
  type: IsmType.Address;
  address: Address;
}

• update all references to use this new object type instead of just a string

Should also tidy up all the if (typeof config === 'string') cases we have scattered around as part of this